seaberg



No. 6|7,|94. Patented Jan. 3, I899. G. SEABERG.

AUTOMATIC LOOK FOR DUMB WAITEBS.

(Application filed Jan. 6, 1898.) (No Model.)

2 Sheets-Sheet l.

WITNESSES n4: "cams PETERS ca, PHoYaun-w WASHINGTDN. n c

No. 6l7,l94. Patented Jan. 3, I899. G. SEABEBG.

AUTOMATIC LOOK FOR DUMB WAITERS.

(Application fllod Jan. 6, 1 898) V 2 Sheets-Sheet 2.

(No Model.)

INVENTOH A TTOHNE rs.

lliviTEn- STATEs PATENT EETCE.

GUSTAVE SEABERG, OF NEW YORK, N. Y.

AUTOMATIC LOOK FOR DUMB-WAITERS.

SPECIFICATION forming part of Letters Patent No. 617,194, dated-January 3, 1899.

Application filed January 6, 1898. Serial No. 665,828. (No model.)

To all whom it may concern.-

Be it known that I, GUSTAVE SEABERG, of New York, (Brooklyn,) in the county of Kings and State of New York, have invented a new and Improved Automatic Lock for DumblVaiters, of which the followingis afull, clear, and exact description.

My invention relates to an improvement in the hoisting devices fordumb-waiters and the object is to provide them with an automatic lock of improved construction which will engage the same to hold the waiter wherever stopped and to prevent the rotation of the supporting-shaft in either direction when the effort is applied thereto by the pulley carrying the hoisting-rope, and yet to leave the same free to rotate easily in either direction when the hand-operated rope is pulled.

The invention consists of certain details of construction which will be hereinafter described and claimed,

Reference is to be had to the accompanying drawings, forming a partof this specification, in which similar characters of reference indicate corresponding parts in all the views.

Figure l is a side elevation of the mechanism for hoisting and supporting the dumb waiter. Fig. 2 is a longitudinal sectional elevation of the same. tion of the same. Fig. 4 is a cross-sectional elevation taken between the sheave-wheel or pulley and the clamping mechanism, showing the clamping mechanism; and Fig. 5 is a side elevation of one of the clamping-disks.

The most common form of supporting and hoisting mechanisms for dumb-waiters consists of a shaft having apulley thereon, over which passes the hoisting-rope, and to one end of which the dumb-waiter is attached and to and will operate as well with. the waiter supported from one side of the pulley as from the other. This mechanism comprises, first, a

Fig. 3 is a horizontal secshaft A, similar to the shaft ordinarily used and mounted horizontally to rotate in suitable bearings at the top of the elevator-well. This is provided with a sheave-wheel or pulley A, adapted to receive a rope A which maybe engaged by hand to raise or lower the dumb .-waiter. This shaft is also provided with a sheave or pulley B, mounted loosely thereon and held in place by a collar 0, which is secured upon the shaft, and by engagement with the clutch or locking mechanism. Upon this same shaft A are loosely mounted two disks D and E. The outer edges of these disks are inclosed by a casin g which is formed in two parts, one part F being bell-shaped and mounted upon supporting-beams and having one of the bearings for the shaft A therein. The disks D E are respectively pro vided with double inclines d 6. These inclines are oppositely arranged upon the same disk and also between the two disks. When placed in proper position, the surfaces of the inclines are in engagement with each other, and the disks are separated only by the height of one of the inclines. If one of these disks be rotated relatively to the other, one of the inclines on each disk will rotate upon a corresponding incline on the other disk and separate the disks. It follows from this construction that the disks will be separated by relative rotation in either direction.

One of the disks D is provided with laterally-extending lugs D, which are provided upon their inner sides with a groove or channel adapted to receive the radial ribs 19 upon the hub B of the sheave-wheel B, which supports the dumb-waiter. By this means the disk D is locked to rotate with the sheave B, but when released may have a slight movement endwise of the shaft A. Each of the disks D and E is provided with segmental slots 6 and (Z. A collar G is secured to the shaft A within the bell of the casing F and is provided with an arm 9', adapted to enter the slots e and d. These slots are of such size as to permit a limited rotation of the arm g before engagement with the edges of the slots.

The casing formed by the two pieces F and F is provided with friction-surfaces f, closely embracing the outer side edges of the disks D and E, so that when the disks are sepasecure a partial balance of the disk.

rated they will engage these friction-surfaces and be held against rotation. In their normal position the slots cl and c in the two disks are in exact register with each other, so that rotation of the arm Q will result in engagement with the ends of the slots in both disks at the same time, and there will consequently be no rotation of one disk relative to the other. If, however, one of the disks has been rotated relatively to the other so as to bind the disks upon the casing a rotation of the arm y will result in bringing the two disks to their normal position, and thus to relieve the friction.

The operation of my device is as follows: \Vhen a pull is applied to the rope A by which the dumb-waiter is operated, the shaft is rotated and the arm g engages one of the ends of the slots in the disks D and E, thus throwing them both into the position where they are freed from the casing. In consequence the pulley B is rotated by a positive connection with the shaft through the disk D and arm g. If the operating-rope A is released, the weight of the dumb-waiter will tend to rotate the pulley B. This will result in a backward rotation of the disk D, and with it of the arm g and shaft A. The disks D and E are, however, in slight frictional contact with the casing at all times. Consequently the friction between the disk E and the casing is greater than the friction between the disk E and the shaft and the disk will not be rotated backward. As a result of this the two disks will be separated by engagement of their inclines c and d. This will result in forcing the disks against the frictional surfaces J until they are securely held thereto. This requires but a small amount of relative rotation between the two disks, an amount which is provided for by the length of the slots 6 and (Z.

It is immaterial in which direction the rotation of the pulley Bis accomplished. The result will be the same. The device may thus be used with the rope passing over either side of the pulley, and is therefore both right.

and left handed in its operation.

For the purpose of securing a more exact balance of the disk E and to eliminate the action of gravity upon an unbalanced disk the disk E is provided with two slots 6 upon opposite sides of the center, so located as to Only one of these slots is necessary for the operation of the device. The other slot may be omitted, if desired; but it is preferable that this or other equivalent means be adapted for balancing the disks.

Having thus described my invention, I claim as new and desire to secure by Letters Patent 1. An automatic lock for dumb-waiters, comprising a shaft having rotating means connected thereto, a hoisting mechanism comprising apulley loosely mounted on said shaft and having radial ribs upon opposite sides of its hub, two disks loosely mounted upon said shaft and having inclines adapted to separate said disks when they are given a relative rotation in either direction, each disk having a segmental slot, the said slots being in registration when the disks are in normal position, one of said disks having projections provided with grooves or channels to engage the radial ribs upon the pulley to secure rotation therewith,a lixed casing embracing said disks, the outer faces of the said disks adjacent to the periphery engaging the casing when the disks are separated and an arm fixed to the shaft within the casing and projecting through the slots in both disks, substantially as described.

2. An automatic lock for dumb-waiters, comprising a shaft having a hand-operated rotating means connected thereto, a hoisting mechanism comprising a pulley loosely mounted upon said shaft and having radial ribs upon its hub, two disks loosely mounted upon said shafts and having inclines adapted to separate said disks when they are given a relative rotation in either direction from the normal, one of said disks having laterallyprojecting lugs each provided with a groove or channel adapted to receive the radial ribs upon the hub of the pulley to secure rotation therewith and each of said disks being provided with a segmental slot, a fixed casing embracing said disks, and in which one of the ends of the said shaft is journaled, the said casing being engaged by the said disks when the latter are separated, and a collar secured to the shaft within the casing and provided with an arm adapted to enter the slots in the said disks, substantially as described.

GUS'PAVE SEABERG. Witnesses:

LEONARD Ross WINTERs, O. B. MOODY. 

